The Biotechnology Unit is responsible for the production and purification of biological material. The Unit undertakes a wide array of biological production tasks such as large-scale growth of procaryotic cells and eucaryotic cells, production of various compounds from microorganisms and eucaryotic cells, and purification of biological compounds especially proteins. These products, not available from commercial sources, are needed for clinical and structural studies. The Biotechnology Unit is capable of handling various production problems associated with widely different topics by implementing both physiological and technical approaches. Efficient process development and production is possible since the Unit possesses two integrated elements: a fully operational multi- purpose pilot production facility and the capability of conducting research and process development. During the last year the Unit performed approximately 200 different large-scale preparations: (1) growing various microorganisms such as recombinant E. coli, recombinant yeast, Corynebacteria diphtheria, Vibrio cholera, and several types of Shigella; (2) propagating large volumes of various mammalian cells; and (3) purifying gram quantities of several proteins such as CRM (cross-reacting material) diphtheria toxin and bovine S antigen. The Unit concentrates on the development of more efficient methods for protein recovery. In this area research was conducted for the use of expanded bed technique for the recovery of both intracellular and extracellular proteins. A new method for propagating of anchorage dependent mammalian cells for the production of secreted proteins was also introduced.